Linguistic Deterioration in Alzheimer's Senile Dementia and in Normal Aging.

Emery, Olga Beattie

A study of language patterning as an indicator of higher cortical process focused on three matched comparison groups: normal pre-middle-aged, normal elderly, and elderly adults with senile dementia Alzheimer's type. In addition to tests of memory, level of cognitive function, and organic deficit, the formal aspects of language were analyzed in these 60 individuals through tests of phonology, morphology, syntax, and semantics. Significant differences in linguistic processing between the comparison groups were found, and the findings suggest that there is a fundamental correlation between the degree of organic impairment and the degree of linguistic decrement, and a direct relationship beween normative denotation and connotation and organic intactness. The process of senile dementing appears to be a process of dedifferentiation in which the person can no longer respond to complexities of the cortical realm. The progressive incapacity of the elderly person with Alzheimer's dementia to code and decode within the normative range is similar to a process of desocialization, and in this process, the two lines of thought and language, or meaning and sound, which merged at one point in development, now begin to separate. A direct relationship is found between linguistic deficits and linguistic complexity, with a concomitant inverse relationship between linguistic deterioration and sequence in language development. Tables and references conclude the document. (MSE)